Lynn M. Highland

Economic and Social Impacts of Landslides

The Session, Socioeconomic Impacts of Landslides, was organized to provide discussions on the socioeconomic impact of landslide events as well as best practice for mitigation of the risk associated with landslides. Social and economic losses, and their quantification, the consequences of landslides on infrastructure development, and land use policy, are critical aspects of socio-economic issues related to landslides. In addition the session will include case studies on recovery and resettlement, measures to reduce social vulnerability, investments for landslide risk mitigation and reduction, and insurance issues for landslide risk mitigation and reduction.

Key factors influencing the mechanism of rapid and long runout landslides triggered by the 2008 Wenchuan earthquake, China

BackgroundThe 2008 Wenchuan earthquake triggered many rapid and long runout landslides, which directly caused great loss of property and human lives and were responsible for a large percentage of total damages caused by the earthquake. It is very important for the purposes of landslide disaster prevention and mitigation to understand the earthquake triggered mechanism of initiation and motion of rapid and long runout landslides, which can potentially be the deadliest of ground failures.ResultsIn this paper, field investigations of some highly damaging landslides caused by the Wenchuan earthquake are introduced first, and followed by data from ring shear tests used to simulate the initiation and motion of one landslide in particular, the Donghekou complex landslide.ConclusionsIt was found that groundwater and valley water played key roles in the rapid motion and long runout process of this landslide during the great earthquake.

Estimation of Direct Landslide Costs in Industrialized Countries: Challenges, Concepts, and Case Study

This paper presents a short summary of the challenges and concepts in previous landslide loss studies and introduces a methodological framework for the estimation of direct landslide costs in industrialized countries. A case study of landslide losses for federal roads in the Lower Saxon Uplands (NW Germany) exemplifies the application of this methodology in a regional setting.

Landslides and engineering geology of the Seattle, Washington, area

This volume brings together case studies and summary papers describing the application of state-of-the-art engineering geologic methods to landslide hazard analysis for the Seattle, Washington, area. An introductory chapter provides a thorough description of the Quaternary and bedrock geology of Seattle. Nine additional chapters review the history of landslide mapping in Seattle, present case studies of individual landslides, describe the results of spatial assessments of landslide hazard, discuss hydrologic controls on landsliding, and outline an early warning system for rainfall-induced landslides.

“Report a Landslide” A Website to Engage the Public in Identifying Geologic Hazards

Direct observation by people is the most practical way of identifying, locating, and describing most damaging landslides. In an effort to increase public awareness of landslide hazards and encourage public participation in collecting basic data about landslides, the USGS recently launched a website called “Report a landslide.” The website is modeled in part after the highly successful USGS website “Did you feel it?” which has been used for several years to gather data from the public about intensity of felt earthquakes. The new “Report a landslide” website encourages visitors to report where and when they observed a landslide and to classify the landslide by movement type. Interested users also can report information about damage and casualties, dimensions, and simple geological observations, and can submit photographs of the landslide. Once a user submits a report, the location of the reported landslide appears on a map, and the location is linked to a summary of submitted data. Photos are reviewed prior to posting on the event page. By adding existing USGS data from historical landslides and promoting the website in the wake of large, regional landslide events, we hope to generate widespread awareness and interest in the website. The “Report a landslide” site has great potential for eventually creating a nationwide source of basic landslide data.

The Landslide Handbook-a Guide to Understanding Landslides: A Landmark Publication for Landslide Education and Preparedness

The International Program on Landslides (IPL) aims to conduct international cooperative research and capacity building on landslide risk mitigation, notably in developing countries. To this end, a proposal was submitted to the IPL project committee by landslide researchers from the Geological Survey of Canada and the U.S. Geological Survey. The proposal is entitled IPL 106 “A Best Practices Handbook for Landslide Hazard Mitigation” and was accepted by the ICL/IPL Board of Representatives (BOR) in 2002. As the project evolved, the aim of the Handbook became more comprehensive and the target audience clarified as those charged with emergency management, landslide mitigation, and public education in both developed and developing countries, including those lay persons interested in a comprehensive introduction to Landslide Hazards. The final product and volume entitled “The Landslide Handbook – A Guide to Understanding Landslides” was written by Lynn Highland, U.S. Geological Survey (Landslide Program) and Peter Bobrowsky, Geological Survey of Canada. This handbook is now helping home-owners, community and emergency managers, and decision makers to take the positive step of encouraging awareness of available options and recourse in regard to landslide hazard. As of 2011 The Handbook has been published in four additional languages: Mandarin Chinese, Japanese, Portuguese, and Spanish.

Initiation and Motion Mechanism of the Donghekou Rapid and Long Runout Landslide Triggered by the 2008 Wenchuan Earthquake, China

The 2008 Wenchuan earthquake triggered many rapid and long runout landslides, which directly caused great loss of property and human lives and were responsible for a large percentage of total damages. For landslide disaster mitigation, it is very important to understand the initiation and motion mechanism of the rapid and long runout landslides, which can potentially be the deadliest of ground failures. In this paper, results of field investigation and ring shear tests simulating the initiation and motion of the Donghekou landslide is presented. It is found that groundwater caused great drop-down of the shear resistance during the initiation and rapid motion of this landslide when it was triggered by the great earthquake.

TXT-tool 0.001-2.1 Landslide Types: Descriptions, Illustrations and Photos

Regardless of the exact definition used or the type of landslide under discussion, understanding the basic mechanics and processes of a typical landslide is critical. With an increasing awareness and mandate to fully understand new building site characteristics, improve existing critical infrastructure and appreciating the importance of an area’s landslide history, typing landslides according to shared characteristics gives vital information about the future performance of a site, in relation to potential landslide hazards. We provide here, a basic primer for an understanding of the similarities and differences of the nature and physics of landslide movement. Type of material, speed of motion, slope angle, potential frequency of occurrence, weather and climatic influences, and man-made disturbances as well as other factors have a bearing on landslide motion, size and impact, yet we can generally group and categorize most landslides into more understandable groupings. Landslide typology is constantly evolving and becoming more exact, given the expanding tools of site investigation, improving computer and GIS modeling, and careful peer analysis.

Environmental Impact of the Landslides Caused by the 12 May 2008, Wenchuan, China Earthquake

The magnitude 7.9 (Mw) Wenchuan, China, earthquake of May 12, 2008 caused at least 88,000 deaths of which one third are estimated to be due to the more than 56,000 earthquake-induced landslides. The affected area is mountainous, featuring densely-vegetated, steep slopes through which narrowly confined rivers and streams flow. Numerous types of landslides occurred in the area, including rock avalanches, rock falls, translational and rotational slides, lateral spreads and debris flows. Some landslides mobilized hundreds of million cubic meters of material, often resulting in the damming of rivers and streams, impacting river ecosystems and morphology. Through an extensive search of both Chinese- and English-language publications we provide a summary of pertinent research on environmental effects, emphasizing key findings. Environmental effects caused by landslides include the alteration of agriculture, changes to natural ecosystems, changes in river morphology due to landslide dams and other effects such as sedimentation and flooding. Damage by landslides to the giant panda reserve infrastructure and habitat, was severe, threatening the survival of one of the world’s rarest species. The Panda reserves are of national significance to China, and to the vital tourism economy of the region. One of the major impacts to both the natural and built environment is the complete relocation of some human populations and infrastructure to new areas, resulting in the abandonment of towns and other areas that were damaged by the earthquake and landslides. The landslide effects have affected the biodiversity of the affected area, and it has been hypothesized that strict forest preservation measures taken in the years preceding the earthquake resulted in a reduction of the environmental damage to the area.